The effects of physical activity level, sex, and different exercise protocols on monocyte TLR expression
Year: 2011
Type: dissertation
Abstract: It has been suggested that moderate exercise contributes to protection against the\ndevelopment of chronic diseases by anti-inflammatory mechanisms that include\nelevations of anti-inflammatory cytokines and also reduction of the expression of Toll-\nLike Receptors (TLRs). However, prolonged strenuous exercise has been shown to\nreduce the function of some immune cells, decrease virus protection and consequently\nmay account for the reason athletes appear more vulnerable to catching Upper\nRespiratory Tract Infections (URTI). Although it has been proven that some exercise is\nbetter than no exercise, it is not clear yet what is the right amount of exercise to elicit\nbeneficial immune responses and to help prevent the development of diseases.\nTherefore, the general aim of the studies in this thesis was to evaluate the impact of\ndifferent types of exercise on monocyte TLR expression in participants with different\nfitness levels. It was found that different acute exercise protocols elicit different\nchanges in TLR2 and TLR4 expression, where an acute bout of strenuous exercise\nreduced TLR4 expression for a few hours after the completion of the exercise (Chapter\n5); however, short two bouts of exhaustive exercise separated by 2 hours did not change\nTLR4 expression (Chapter 6). In addition, changes in TLR4 expression were related to\nsex and the physical activity level of the participants (Chapter 4), and should therefore\nbe considered separately when analysing TLR4 expression. Furthermore, high-intensity\nintermittent training improves participants’ aerobic capacity and modifies the monocyte\nsubpopulation concentration in the blood, with no changes in TLR4 expression. Further\nresearch needs to be done in this area to achieve a conclusive finding about changes in\nTLR4 expression and monocyte subsets after different training protocols, and possible\nrelationships to cytokine production.
Author: Marta Oliveira
Language: English
Subfield: Physiology (medical)
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2620495722